I frequently have to copy files from 1 folder to 2 different other folders (to another internal HDD and to a backup external USB Drive).
Right now I wait until 1 task is done before starting the other so to avoid possible(?) conflicts. The jobs are not queued but run at the same time then
I did to run the two copy tasks almost immediately after each other and it seems that things are fine. Nonetheless I wonder whether there is any risk in doing so (conflicts), considering that the jobs aren't queued but in fact run in two separate copy sessions.
Leo, to be honest, I don't mind whether in queue or simultaneously. If there are no conflicts whilst copying simultaneously, then fine.
I meant to say, when 2 jobs run simultaneously processing the same source folder, then the 2nd run may try to access a file that is being processed by the first run. What happens then? Will the 2nd job skip that file and take another file for the time being?
As said, I did give it a try with some large folders and large sized files, so both runs were busy for a while. There were no issues, all files were copied fine. Until now I have always been a bit careful doing such simultaneous copies (or better: I refrained from doing it) as I wasn't sure.
Hence the question.
If they are both reading from the same file/directory then it doesn't matter. (It might be a bit slower as the source disk has to go back & forth between the two operations, but it will work fine. Caching might also mean it is actually faster, too, depending on whether the two copies keep pace with each other or not.)
You only want to avoid two ore more things writing to the same file at once. Reading from the same file is not a problem.